It started when Oregon Sen. Ron Wyden -- the top Democrat on the Senate Finance Committee -- opened with a tough statement about financier Steven Mnuchin.

That led a Republican senator, Pat Roberts, of Kansas, to suggest that Wyden might want to take the sedative Valium. Roberts also said Wyden had suggested the former banker Mnuchin was "in charge of the Great Recession."

After Roberts' attempt at humor, Democratic Sen. Sherrod Brown, of Ohio, jumped into the fray and said Roberts' Valium comment was "just outrageous."